The serve is the most important factor on the ATP Tour besides consistency.
Not only do you need a decent return of serve but you certainly need to be able to hit your spots and get on top of the point as soon as possible when it comes time to serve.
This slideshow compiles a list of and acknowledges the top 10 servers in the game that give even the best returners a great deal of trouble.
These serves are ranked in order based on the speed, ability to hit spots, angle or trajectory of the ball, difficulty to return and ability to finish the point on the next shot.
Though his form, stature and ball toss are incredibly wacky and unpredictable his serve is one of the most powerful in the game.
Unfortunately his serve and winning ways can be just as inconsistent as his ball toss and that is why he has yet to make an impact for his country like so many of his fellow players have.
He has the ability to hit crazy serves out to the forehand on both sides and stretches his arm over the middle of the baseline to add angle.
The man who is married to Jarmila Gajdosova is more famous for a certain shot of his.
Breaking Ivo Karlovic's previous record for the world's fastest serve by 12 kilometers per hour, this Australian player may very well hold that record for many years to come. For that, he gets a spot on this list.
There is no question that the tall-standing Argentine is powerful all-around.
His serve has lost some direction since his elbow injury and he seems to be having tougher service holds than usual. Nevertheless, he has remained dominant by holding serve and challenging opponents during return games, and this is why he is especially dangerous.
One of the more underrated players—Gilles Muller—has some pop on his serve.
The lefty's spin mixed with his hard-to-read direction and spot-serving makes him a dangerous floater.
He certainly lacks consistency and does not play pressure points all that well when he misses the first serve.
Though he loses tight battles to top players often his serve is still a huge weapon and allows him to compete at the top level.
Another tall-standing athlete that has a monster serve would be this South African player.
He is able to hit great angles and get extra kick on his second serve because of his height and strength.
Though his second serve does not always draw weak returns he has a great one-two punch and finishes off points immediately. He has challenged the top players and is a rising star in the circuit.
Jo is not only the best French player out there but he is also one of the only ones with a truly powerful serve. The other French players, including Julien Benneteau, Michael Llodra and Richard Gasquet, have to work harder to win points.
His charisma and overall talent add to his monstrously scary and varied serve.
Perhaps one of the slowest servers on this list in terms of speed, Roger Federer still holds serve more than a majority of them.
This is due to his spot serving, pinpoint accuracy and ability to finish off points on the next shot or at the net.
His toss is nearly identical every time and, even when his percentage dips late in matches, he still finds a way to hold and make it matter. His consistency with his serve is almost as unparalleled as his career consistency.
The most powerful player on tour in my opinion—Tomas Berdych—is a threat to everybody in every tournament.
He is a very complete player that gets ahead in service games by bombing aces in each direction.
Though his kick serve is a bit weaker than some of his competitors he tends to have a very high first serve percentage.
For some reason he falls to very low-ranked opponents from time to time but there is no question that it is difficult to break this man's serve.
The American famous for his serve and big follow-up forehand, John Isner, is reliant upon these two shots in each and every match.
Due to his unusual height he continues to have a high first serve percentage. He also has the freedom to go for big second serves, much like the server in the No. 1 spot.
His game may not be able to improve much more but it may never have to.
The "still up-and-coming" talent from Canada has become a true threat to the world's best for a few reasons.
One would be his newly fixed return of serve, which allows him to strike winners off of both wings.
Another is his ability to find the opponent's backhand in ground stroke rallies. But the main reason he is so successful is his unprecedented serve.
It has significant pop, kick, speed, angle and goes in (as aces) frequently.
Keep an eye out on this man to continue to ascend to the top of the rankings.
The number one server has not changed in the past few years, though his winning percentage is certainly not up there with some of the others.
Ivo Karlovic, the tallest men's player, is not very quick on his feet or good at hitting backhands. Instead he makes up for it by cracking forehands in short rallies and coming to net to finish off points.
Though he cannot break serve efficiently he is almost certain in matches that he can at least hold five or six consecutive games to get to a tiebreak. This is because his serve is ridiculously quick, is hardly returned cleanly and forces opponents to go for broke.
The trajectory at which the ball is struck makes the ball bounce significantly higher out of the service box than all other servers, which makes his serve very tough to return and even practice for.
Seeing his name in the draw is definitely not a good thing when you have an average serve.
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